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Has the signal ever repeated, and what would a search need to find out?

Asked 26 Oct 2026 by ·3 answers·0·0 following
Most likely: the source does not repeat on any timescale sampled so far (seconds to decades)Ahead on the evidence, not yet confirmed. It needs two reviews to be accepted.

Where it stands

Three answers have been proposed. The source does not repeat on any timescale sampled so far (seconds to decades). leads, with evidence 2 for: partly supported by its tests. Two are still possible.

Why it matters

Repetition is the one test that could settle the case, and the question of how much observing is enough is quantitative⁠[1]⁠[2].

Answers 3

Evidence: 2 for
Most likely
None of these.
Not tested enough to call either way
Evidence: none yet
Still possible
Evidence: 1 for
Still possible

History

  1. Gray & Ellingsen puts forward: the source does not repeat on any timescale sampled so far (seconds to decades).
  2. Kipping & Gray puts forward: the source repeats on a schedule the follow-ups have not sampled (random repeater or long period).
  3. Kipping & Gray: strictly periodic sources with periods under about 40 hours are excluded.For: The source does not repeat on any timescale sampled so far (seconds to decades).
  4. Kipping & Gray: a stochastic repeater is compatible with the Big Ear logs and only in 2.4-sigma tension with 192 hours of…For: The source repeats on a schedule the follow-ups have not sampled (random repeater or long period).
  5. Méndez et al.: about a hundred follow-ups over four decades, including the VLA, META and Hobart, found no signal.For: The source does not repeat on any timescale sampled so far (seconds to decades).
  6. Asked on this site
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